x+19x=4,x+19x=4,x + \frac{1}{{9x}} = 4{\text{,}} then 9x2+19x2" role="presentation">9x2+19x29x2+19x2{\text{9}}{x^2} + \frac{1}{{9{x^2}}} is?" /> x+19x=4,x+19x=4,x + \frac{1}{{9x}} = 4{\text{,}} then 9x2+19x2" role="presentation">9x2+19x29x2+19x2{\text{9}}{x^2} + \frac{1}{{9{x^2}}} is?" /> x+19x=4,x+19x=4,x + \frac{1}{{9x}} = 4{\text{,}} then 9x2+19x2" role="presentation">9x2+19x29x2+19x2{\text{9}}{x^2} + \frac{1}{{9{x^2}}} is?" />

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If $x + \frac{1}{9 x} = 4,$ $x + \frac{1}{{9x}} = 4{\text{,}}$ then $9 x^{2} + \frac{1}{9 x^{2}}$ ${\text{9}}{x^2} + \frac{1}{{9{x^2}}}$ is?

1140
2142
3144
4146

Answer:- 1

Explanation:-

Solution:

\begin{aligned} x + \frac{1}{9 x} = 4 \\ Multiply by 3 both side \\ \Rightarrow 3 x + \frac{1}{3 x} = 12 \\ Squaring both sides \\ \Rightarrow 9 x^{2} + \frac{1}{9 x^{2}} + 2 \times 3 x \times \frac{1}{3 x} = 144 \\ \Rightarrow 9 x^{2} + \frac{1}{9 x^{2}} + 2 = 144 \\ \Rightarrow 9 x^{2} + \frac{1}{9 x^{2}} = 142 \end{aligned}

$\eqalign{ & {\text{ }}x + \frac{1}{{9x}} = 4 \cr & {\text{Multiply by 3 both side}} \cr & \Rightarrow {\text{3}}x + \frac{1}{{3x}} = 12 \cr & {\text{Squaring both sides}} \cr & \Rightarrow {\text{9}}{x^2} + \frac{1}{{9{x^2}}} + 2 \times 3x \times \frac{1}{{3x}} = 144 \cr & \Rightarrow {\text{9}}{x^2} + \frac{1}{{9{x^2}}} + 2 = 144 \cr & \Rightarrow {\text{9}}{x^2} + \frac{1}{{9{x^2}}} = 142 \cr}$

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then

9 x^{2} + \frac{1}{9 x^{2}}

${\text{9}}{x^2} + \frac{1}{{9{x^2}}}$ is?", "text": "If

x + \frac{1}{9 x} = 4,

$x + \frac{1}{{9x}} = 4{\text{,}}$ then

9 x^{2} + \frac{1}{9 x^{2}}

${\text{9}}{x^2} + \frac{1}{{9{x^2}}}$ is?", "dateCreated": "7/24/2019 10:09:12 AM", "author": { "@type": "Person", "name": "Nitin Sir" }, "answerCount": "4", "acceptedAnswer": { "@type": "Answer", "text": "

Solution:

\begin{aligned} x + \frac{1}{9 x} = 4 \\ Multiply by 3 both side \\ \Rightarrow 3 x + \frac{1}{3 x} = 12 \\ Squaring both sides \\ \Rightarrow 9 x^{2} + \frac{1}{9 x^{2}} + 2 \times 3 x \times \frac{1}{3 x} = 144 \\ \Rightarrow 9 x^{2} + \frac{1}{9 x^{2}} + 2 = 144 \\ \Rightarrow 9 x^{2} + \frac{1}{9 x^{2}} = 142 \end{aligned}

$\eqalign{ & {\text{ }}x + \frac{1}{{9x}} = 4 \cr & {\text{Multiply by 3 both side}} \cr & \Rightarrow {\text{3}}x + \frac{1}{{3x}} = 12 \cr & {\text{Squaring both sides}} \cr & \Rightarrow {\text{9}}{x^2} + \frac{1}{{9{x^2}}} + 2 \times 3x \times \frac{1}{{3x}} = 144 \cr & \Rightarrow {\text{9}}{x^2} + \frac{1}{{9{x^2}}} + 2 = 144 \cr & \Rightarrow {\text{9}}{x^2} + \frac{1}{{9{x^2}}} = 142 \cr}$ ", "dateCreated": "7/24/2019 10:09:12 AM", "author": { "@type": "Person", "name": "Nitin Sir" } }, "suggestedAnswer": { "@type": "Answer", "text": "

Solution:

\begin{aligned} x + \frac{1}{9 x} = 4 \\ Multiply by 3 both side \\ \Rightarrow 3 x + \frac{1}{3 x} = 12 \\ Squaring both sides \\ \Rightarrow 9 x^{2} + \frac{1}{9 x^{2}} + 2 \times 3 x \times \frac{1}{3 x} = 144 \\ \Rightarrow 9 x^{2} + \frac{1}{9 x^{2}} + 2 = 144 \\ \Rightarrow 9 x^{2} + \frac{1}{9 x^{2}} = 142 \end{aligned}

$\eqalign{ & {\text{ }}x + \frac{1}{{9x}} = 4 \cr & {\text{Multiply by 3 both side}} \cr & \Rightarrow {\text{3}}x + \frac{1}{{3x}} = 12 \cr & {\text{Squaring both sides}} \cr & \Rightarrow {\text{9}}{x^2} + \frac{1}{{9{x^2}}} + 2 \times 3x \times \frac{1}{{3x}} = 144 \cr & \Rightarrow {\text{9}}{x^2} + \frac{1}{{9{x^2}}} + 2 = 144 \cr & \Rightarrow {\text{9}}{x^2} + \frac{1}{{9{x^2}}} = 142 \cr}$ ", "dateCreated": "7/24/2019 10:09:12 AM" } }

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